How To Open Image In Picasa Photo Viewer

You Can Do this.         
           string file = @"C:\Sunset.Jpg";
            ProcessStartInfo pi = new ProcessStartInfo(file);
            pi.Arguments = Path.GetFileName(file);
            pi.UseShellExecute = true;
            pi.WorkingDirectory = Path.GetDirectoryName(file);
            pi.FileName = @"C:\Program Files\Google\Picasa3\PicasaPhotoViewer.exe";
            pi.Verb = "OPEN";
            Process.Start(pi);

I hope This is Work For you.